1. Field of the Invention
The present invention relates to an arrowhead and an arrow, and more particularly, to an arrowhead having expanding blades.
2. Discussion of Related Art
In general, an arrow includes an arrow shaft made of a hollow pipe body, an arrowhead installed at a front end of the arrow shaft, an arrow notch for fitting the arrow on a bowstring, and arrow feathers for securing flight stability of the arrow.
Among these, the arrowhead serves to substantially penetrate a target. Since energy accumulated in the arrow is concentrated on the arrowhead at a moment at which the arrow hits its target, the arrow should have excellent wear resistance and strength and should also have a structure enabling the arrow to fly stably.
Generally, the arrow has a sharpened upper end in order to provide great penetration power. However, an arrowhead having excellent penetration power may not be suitable for particular hunting purposes. This is because sharp arrowheads may not deliver a deadly wound to larger game and thus it is difficult to quickly subdue the game. Therefore, in view of this point, 2 to 4 sharp blades may be provided at an edge of a sharp arrowhead. Alternatively, a broadhead for inducing severe bleeding may be used.
Meanwhile, since the blades provided at an edge of the broadhead of the arrowhead may affect the flight stability of the arrow, various kinds of arrowheads having a structure in which the blades may normally fold inward and then unfold upon hitting a target are already well known.
A blade having such an unfoldable structure is called an expanding blade. Such expanding blades are disclosed in many patent documents, such as U.S. Pat. No. 5,082,292 entitled “BROADHEAD WITH DEPLOYABLE CUTTING BLADES,” U.S. Pat. No. 5,066,021 entitled “ARROW SYSTEM,” U.S. Pat. No. 4,973,060 entitled “ARROWHEAD WITH EXPANDABLE BLADES,” U.S. Pat. No. 6,669,586 entitled “EXPANDING BROADHEAD,” U.S. Pat. No. 6,258,000 entitled “PENETRATION ENHANCING AERODYNAMICALLY FAVORABLE ARROWHEAD,” U.S. Pat. No. 6,287,223 entitled “DULLING PREVENTION FOR SHARP CUTTING EDGE OF BLADE-OPENING ARROWHEAD BLADES WHEN IN A CLOSED IN-FLIGHT POSITION,” U.S. Pat. No. 8,062,155 entitled “ARROWHEAD HAVING BOTH FIXED AND MECHANICALLY EXPANDABLE BLADES,” and U.S. Pat. No. 6,200,237 entitled “SLIDING BODY EXPANDING BROADHEAD.”
In all of these patent documents, 2 to 4 expanding blades are provided. When the arrow hits a target such as game, the multiple expanding blades unfold in order to dig up a wounded area of the game, penetrate more deeply, and thereby increase killing power.
However, in the conventional expanding blades, there is a disadvantage in that, after the arrow is shot, the expanding blades unfold by themselves during flight and thus have a bad effect on flight stability, accuracy rate, and a flight distance of the arrow.
Further, after the arrow hits its target, the expanding blades may abnormally fold due to movement of the target or the like, and thus the bleeding may not be induced any longer.
Therefore, it is necessary to develop a new arrowhead having a structure in which the folded expanding blades do not unfold by themselves during flight of the arrow and thus the arrow may fly stably, and the expanding blades automatically unfold only when the arrow hits its target, and are also maintained in the unfolded state after the arrow hits its target.